Toni Kroos plays the ball into the feet of Cristiano Ronaldo. With a defender on his back, the Portuguese gathers, spins in a flash and launches a vicious left-footed shot that is fortunately blocked.

Cordoba escape. But a marker has been laid.

Real Madrid push forward in the 87th minute.

Pepe picks out LukaModric in space in midfield. With consummate ease, the Croatian pivots, settles and feeds a perfectly weighted ball to Ronaldo, who nonchalantly slides it into the net.

Offside is called. The goal doesn't count.

Cordoba escape. But another marker has been laid.

Real Madrid push forward in the 90th minute.

Isco wins possession in midfield, poking the ball to a free Ronaldo. Taking just two touches to set an explosive platform, the Ballond'Or winner launches a lethal long-range strike with his right boot that thunders into the bottom corner past Juan Carlos.

Cordoba don't escape. Real Madrid 2-0.

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Ronaldo's four-minute burst to conclude Real's La Liga opener neatly encapsulated the devastation his game can wreak. Interestingly, however, his fleeting, late barrage on Cordoba's goal—a passage that was hardly a recurring theme throughout the night—was also reflective of his health.

Indeed, Ronaldo is rather symbolic of his side at this early stage. Despite appearing to be in supreme condition during the European champion's UEFA Super Cup clash with Sevilla, the 29-year-old's fitness has become a concern once more since he left the field at halftime during the first leg of the Spanish Super Cup against Atletico Madrid last Tuesday.

From that moment, Ronaldo—much like his team—has laboured through a week of football.

On Monday, the Portuguese wasn't close to full health, seen walking on numerous occasions as La Liga's newcomers played out from the back while lacking—until the final four minutes, at least—the explosive capacity one typically associates with the reigning World Player of the Year.

Brief moments of excellence, of course, were enough against Cordoba. But such a cameo can't mask the uneasiness surrounding the fitness of Real's biggest star.

"I wonder if this is the season where Ronaldo discovers the limits of his body," GuillemBalaguewrote last week.

With a lingering patellar tendon issue, that's suddenly possible.

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Pinpointing the roots of Real Madrid's rather lacklustre recent displays hasn't been straightforward, but Ronaldo's questionable injury status has undeniably been a factor.

While it's easy to suggest Carlo Ancelotti's tinkering of the system to accommodate James Rodriguez is largely responsible, it's Ronaldo's health—or lack thereof—that has contributed to the need for a change in shape, as illustrated below.

Unable to rely upon his main weapon to be his usually barnstorming presence on the wing, Ancelotti's formation has become something of a 4-4-2, with Ronaldo joining Karim Benzema centrally at the head of the attack, thereby reducing the Portuguese's workload.

Yet the result has been Rodriguez's relegation to the flank, denying the Colombian of his preferred No. 10 role in a 4-2-3-1, concurrently stripping Real Madrid of a player capable of operating between the lines in the way Angel Di Maria did last season.

Suddenly, a team who thrived in a 4-3-3 last term have found themselves caught somewhere between that system and two others in the early weeks of the current campaign.

The integration of club president Florentino Perez's shiny new acquisitions has been a contributing influence, but so too has Ronaldo's sub-optimal health that has forced a change in his positioning.

Daniel Ochoa de Olza/Associated Press

So do Real ride out their main star's injury concerns, trusting that an athlete of his calibre will eventually shrug aside those issues? Or should the club be looking to quell Ronaldo's immediate involvement, taking his body—or, more specifically, his knee—away from the rigours of the game and the intensity of his play?

Given Ronaldo's thirst for competition and his unchallenged standing at the Bernabeu, the former would appear more likely.

There's a fine line being approached, one feels.

Thus, the fitness of Los Blancos' major drawcard looks set to be a major point of focus in the coming weeks and months. While his teammates possess enough sumptuous talent of their own, Real Madrid's elusive quest for both attacking perfection and unrivalled European dominance can't be achieved without Ronaldo.

The supporting cast may be stellar, but it's Ronaldo's unrelenting brilliance that lies at the heart of the continental champions' success. In recent days, concerns have arisen about his body's ability to sustain such a level.